Method for direct seeding and seedling cultivation of Bletilla striata seeds using a matrix containing Bacillus velezensis

Abstract

The present invention belongs to the technical field of Chinese medicinal material seedling cultivation, and specifically relates to a method for direct seeding of Bletilla striata seedlings using endophytic bacteria thereof, comprising obtaining Bletilla striata seeds, sowing, seedbed management, transplanting and fostering the seedlings; the nutrient soil on the seedbed is composed of a bacterial bottom matrix and a bacterial top matrix; first, a bottom matrix with a thickness of 6 to 7 cm is laid on a non-woven fabric; a Bacillus velezensis liquid is sprayed on the bottom matrix; then, clean water is sprinkled and stirred evenly until a bacterial bottom matrix with a moisture content of 60 to 70% is obtained; a Bacillus velezensis liquid is sprayed on the top matrix, then, clean water is sprinkled and stirred evenly until a bacterial top matrix with a moisture content of 60 to 70% is obtained; the bacterial top matrix is laid on the bacterial bottom matrix to a thickness of 5 to 6 cm, and then compacted to obtain the nutrient soil. The method of the present invention can ensure the survival rate of Bletilla striata seedlings after transplanting and enhance their competitiveness with field weeds.

Description

Technical Field

[0001] The invention belongs to the technical field of Chinese medicinal material seedling cultivation, and particularly relates to a method for direct seeding of Bletilla striata seedlings by utilizing endophytic bacteria of Bletilla striata. Background Art

[0002] Bletilla striata is a traditional and precious Chinese medicinal herb. It is a perennial herbaceous plant of the genus Bletilla in the Orchidaceae family, used for its dried tubers. Wild Bletilla striata is found at altitudes between 400 and 3,200 meters in moist mossy beds and rocky cliffs, often associated with shrubs. It can also grow at forest edges, away from direct sunlight, or in cool, moist, well-drained humus soil and fertile sandy loam. Due to overexploitation, wild Bletilla striata resources are now nearing depletion, and artificial cultivation has become the primary method. However, due to its small seeds and lack of endosperm, Bletilla striata is difficult to germinate under natural conditions. Traditionally, Bletilla striata tuber seedlings have been used, but this method requires a large number of tubers, results in a low and slow reproduction rate, a long seedling production cycle, and high production costs. In recent years, the propagation of Bletilla striata seedlings through tissue culture has reduced the cost of Bletilla striata production compared to tuber seedlings. However, tissue culture itself requires expensive facilities and equipment, and a foster care process, which prolongs the time required for seedling cultivation and is not conducive to reducing the cost of Bletilla striata seedlings. Therefore, using Bletilla striata seeds for artificial direct seeding is an ideal way to raise seedlings.

[0003] The endophyte Bacillus Velezii is isolated from the Bletilla striata plant and can produce a variety of plant hormones such as KT, SA and 6-BA, which have a significant promoting effect on the growth of plants such as Bletilla striata (Zhao Yin, Breeding Technology of High-Quality Seedlings of Bletilla striata and Screening and Identification of Growth-Promoting Endophytes, Master's Thesis, Zhejiang University, 2020).

[0004] The invention of CN110338047B, "A method for efficiently raising seedlings of Bletilla striata seeds by direct seeding in a simulated wild manner," states that it includes the following steps:

[0005] S1. Processing of Bletilla striata pods: In September and October, when the shell of Bletilla striata pods turns yellow, pick the pods with the stems and dry them in the shade. When the pods become crisp and the color changes from green to brown, store them at a constant temperature of 4°C for later use.

[0006] S2. Greenhouse and water source system establishment: Select fields in areas with convenient water sources to build steel-frame greenhouses, cover them with agricultural film, cover the film with sunshade nets, and set up atomizing micro-spraying pipes inside the greenhouses;

[0007] S3, seedling pool laying: ridges are raised in the greenhouse in step S2 and leveled for use, leaving rows of work between the ridges, and several bamboo stakes are inserted on both sides of the ridges. The bamboo stakes are used as support to stand several plastic hollow boards on both sides of the seedling box, and the seedling box is laid with agricultural film and fixed with plastic hollow boards on both sides, and holes are punched in the film at the bottom of the seedling box;

[0008] S4, laying the medium in the nursery pond: spraying abamectin on the film in step S3, then laying peat soil, laying the drug residue matrix on the peat soil, spraying water into the nursery pond, and adjusting the soil pH with acetic acid and citric acid;

[0009] S5, sowing: the seeds in the bletilla striata fruit pod are pressed out, the fruit pod shell is removed, the bletilla striata seed powder is sieved and evenly sown on the nursery pond compartment surface in step S4, and the nursery pond compartment surface in step S4 is sprayed with direct seeding nutrient solution I the next day after sowing;

[0010] S6. Inoculation of symbiotic bacteria: Inoculate the Bletilla striata symbiotic bacteria using PDB medium, incubate at 28°C, 200 rpm, and incubate for 7 days. Then, crush the bacterial solution. 10 days after sowing the Bletilla striata, when hairy roots differentiate from the enlarged protocorms, spray the bacterial solution on the sowing surface.

[0011] S7. Early water and fertilizer management: From seed sowing until the second true leaf grows, spray water once in the morning and evening every day. Spray with a mixture of acetic acid and citric acid every three days. Apply carbofuran or 8% Duxin granules in the greenhouse every 45 days.

[0012] S8. Water and fertilizer management in the middle and late stages: After 60 to 75 days, when the Bletilla striata grows its second true leaf, water it every 2 to 3 days using a mist sprinkler and spray it with direct seeding nutrient solution II every 7 days.

[0013] S9. Overwintering treatment and seedling acclimation in the second year: In December of the same year, after the Bletilla striata seedlings in the nursery pond have fallen over, use the medicinal residue matrix to cover the Bletilla striata pseudobulbs exposed on the soil surface, maintain the soil moisture content at 35-55%, and prepare for overwintering; in the second year, after the pseudobulbs germinate and emerge from the soil, spray them with direct seeding nutrient solution II once every 10 days.

[0014] The method improves the germination rate of Bletilla striata seeds by more than 60%, and reduces the seedling raising cost by 86% compared with the traditional method. Summary of the Invention

[0015] The technical problem to be solved by the present invention is to provide a method for direct seeding and raising seedlings of Bletilla striata using endophytic bacteria, that is, a method for direct seeding and raising seedlings of Bletilla striata seeds using a matrix added with endophytic bacteria of Bacillus velezensis is disclosed.

[0016] In order to solve the above technical problems, the present invention provides a method for direct seeding and raising seedlings of Bletilla striata seeds for use with a substrate containing Bacillus velezensis, comprising obtaining Bletilla striata seeds, sowing, seedbed management, transplanting and fostering;

[0017] The nutrient soil on the seedbed is composed of a bottom layer matrix containing bacteria and an upper layer matrix containing bacteria;

[0018] First, lay a 6-7 cm thick bottom matrix on the non-woven fabric; the bottom matrix consists of peat: vermiculite: mature organic fertilizer: sediment = 5: (1 ± 0.1): (1 ± 0.1): (3 ± 0.3) by volume, and spray 10 9 CFU / mL / ml of Bacillus velezensis bacterial solution; the Bacillus velezensis bacterial solution: bottom matrix

[0019] =1-2 / 500 (V / V); then sprinkle with clean water and stir evenly until a bacteria-containing bottom matrix with a moisture content of 60-70% is obtained;

[0020] The upper matrix is composed of peat: vermiculite: mature organic fertilizer = 6: (3 ± 0.3): (1 ± 0.1) by volume. Spray 10 9 cfu / ml of Bacillus Velez bacteria liquid, wherein the Bacillus Velez bacteria liquid: upper layer matrix = 1-2 / 500 (V / V); then sprinkle with clean water and stir evenly until a bacteria-containing upper layer matrix with a moisture content of 60-70% is obtained;

[0021] The bacteria-containing upper substrate is laid on the bacteria-containing bottom substrate with a thickness of 5 to 6 cm, and then compacted to obtain nutrient soil.

[0022] As an improvement of the method for direct seeding and seedling cultivation of Bletilla striata seeds containing the Velez substratum of the present invention:

[0023] 1. Sowing:

[0024] 1.1) Set the sowing time:

[0025] When the minimum temperature of the day is ≥15℃ and the average temperature is 24±3℃, sow the seeds of Bletilla striata (direct seeding in matrix);

[0026] 1.2) Establishing the seedbed:

[0027] Establish a seedbed in the greenhouse and lay non-woven fabric on the seedbed;

[0028] 1.3) Preparation of nutrient soil:

[0029] 1.4) Sowing method:

[0030] Add 1.5±0.1g of Bletilla striata seeds and 10±0.5g of talcum powder, mix well, and sieve (through 100 mesh sieve); then evenly sprinkle on the surface of the nutrient soil per square meter of the seedbed to complete the sowing; then lay a thin layer (about 0.4-0.6cm thick) of the upper substrate.

[0031] 1.5) Erect sunshade facilities:

[0032] Install sunshades on top of the seedbed to ensure that the intensity of sunlight in the greenhouse does not exceed 15,000 lux on sunny days;

[0033] 2. Seedbed management:

[0034] Maintain appropriate light, temperature, humidity, and fertilization as follows:

[0035] Light: natural light;

[0036] Temperature: Keep the temperature in the greenhouse at 25±2℃;

[0037] Note: When the temperature is high in summer, in addition to adding sunshade facilities, you should also pay attention to ventilation and cooling of the greenhouse to prevent high temperature from burning the seedlings;

[0038] Humidity: Water in time to maintain the soil moisture content at 13.5-22%;

[0039] Fertilization: After 4 true leaves grow (about 50 days after sowing), spray the diluted nutrient solution once every 8 to 10 days; the nutrient solution contains 10 9 CFU / mL / ml Bacillus velezensis bacterial solution in 10% potassium fulvic acid nutrient solution;

[0040] The containing 10 9 The preparation method of 10% potassium fulvic acid nutrient solution containing CFU / mL / ml of Bacillus velezensis bacterial liquid is as follows: first, potassium fulvic acid and water are mixed in a mass ratio of 1:4 to obtain 20% potassium fulvic acid nutrient solution; then, the 20% potassium fulvic acid nutrient solution is mixed with 2*10 9 CFU / mL / ml Bacillus velezensis bacterial solution was mixed in equal volume ratio;

[0041] Use 2-2.5ml of nutrient solution per square meter of seedbed;

[0042] 3. Transplanting and foster care:

[0043] When the pseudobulbs of Bletilla striata seedlings reach more than 10mm, they can be directly used as seedlings for field planting;

[0044] When the pseudobulb size of Bletilla striata seedlings reaches 6-10 mm, they are used as foster plant seedlings.

[0045] Description: Bletilla seeds will begin to green 7-10 days after sowing; they will germinate 3 weeks after sowing; and the first leaves will appear 30 days after sowing. After about 7 months of cultivation, suitable seedlings for field planting and foster planting can be obtained.

[0046] As an improvement to the method of the present invention: Step 1.2) is as follows: establishing a seedbed in a greenhouse, the seedbed is 1.5 to 2 meters wide and the length is determined according to the length of the greenhouse, the seedbed is leveled and compacted, and insecticide is sprayed (250 ml of 40% phoxim emulsifiable concentrate is used per mu, diluted with 100 liters of water), and then a layer of non-woven fabric is laid on the seedbed, the non-woven fabric being in close contact with the topsoil of the seedbed; the seedbed is surrounded by thin bricks for easy management and operation.

[0047] As an improvement to the method of the present invention: Step 1.5) is: setting a sunshade net with a shading rate of 75% on the top of the seedbed, and adding sunshade facilities in summer to ensure that the intensity in the greenhouse on sunny days is no higher than 15,000 lux.

[0048] As an improvement to the method of the present invention: the step 2 also includes combing the seedlings: according to the emergence of seedlings in the seedbed, in accordance with routine procedures, the diseased seedlings (i.e., the leaves are yellowed) are promptly removed; when the regional density is significantly higher than the surrounding density, the weak seedlings with poor growth are removed until the density is basically the same.

[0049] As an improvement to the method of the present invention: the foster care method in step 3 is:

[0050] Seedbed establishment: The foster seedbed should be established on a relatively high and dry plot of land that is not prone to waterlogging. Sandy loam rich in humus is preferred. The width of the field should be 1.1 to 1.2 meters, the width of the ditch should be 0.25 to 0.3 meters, and the depth of the ditch should be 22 to 25 centimeters (the field should be slightly bun-shaped).

[0051] Base fertilizer: 35kg of calcium magnesium phosphate fertilizer, 5-7.5kg of potassium sulfate compound fertilizer, and 1500kg of decomposed organic fertilizer per mu, raked in with a micro-tillage machine;

[0052] Planting: Planting density: row spacing 10-12*8-10cm, bulbs buried in the soil depth 1.5-2.5cm;

[0053] Light, temperature, humidity and fertilization: Same as the seedbed management in step 2 above.

[0054] The beneficial effects of the present invention are mainly reflected in:

[0055] 1. The present invention sprays the endophyte Bacillus Velez subtilis isolated from Bletilla striata in the matrix, and uses a potassium fulvic acid solution containing Bacillus Velez subtilis as a topdressing fertilizer during the seedling management stage, which has the advantages of fast seed germination, thick and robust seedling leaves, and large pseudobulbs.

[0056] After 7 months of sowing, the average particle size of the pseudobulbs of the invention can reach 7.62 mm.

[0057] 2. The bottom seedling matrix formula of the present invention is preferably peat: vermiculite: mature decomposed organic fertilizer: silt = 5:1:1:3 (volume ratio), and the upper seedling matrix formula is preferably peat: vermiculite: mature decomposed organic fertilizer = 6:3:1 (volume ratio); this formula combination is not only conducive to stabilizing the quality of the matrix, but also conducive to reducing the cost of the matrix.

[0058] 3. The present invention utilizes potassium humate solution as a topdressing ingredient, giving full play to the functions of potassium humate in improving soil, increasing soil fertility, promoting rooting, root nourishment, root strengthening, nitrogen fixation, phosphorus solubilization, and potassium solubilization; thereby enhancing functions such as crop resistance.

[0059] 4. The present invention uses the size of the pseudobulb particle size as the quality standard for evaluating the Bletilla striata seedlings, uses the pseudobulb particle size greater than 10 mm as the standard for field transplanting, and uses the pseudobulb particle size of 6 to 10 mm as the standard for Bletilla striata seedling foster care, thereby ensuring the survival rate of Bletilla striata seedlings after transplanting and enhancing their competitiveness with field weeds. DETAILED DESCRIPTION

[0060] The present invention is further described below with reference to specific embodiments, but the protection scope of the present invention is not limited thereto:

[0061] The Bacillus velezensis of the present invention is derived from Bletilla striata, and Bacillus velezensis ZJU-C612-5 Bacillus velezensis ZJU-C612-5 can be selected.

[0062] The preservation information of the above-mentioned strain is as follows: Deposit name: Bacillus velezensis ZJU-C612-5 Bacillus velezensis ZJU-C612-5; Deposit number: CCTCC NO: M2019838, Deposit unit: China Center for Type Culture Collection, Deposit address: Wuhan University, Wuhan, China, Deposit date: October 18, 2019.

[0063] Example 1

[0064] 1. Selection of seed sources and seed-keeping land

[0065] The local characteristic Bletilla striata with purple flowers was used as the seed source. The seeding site had good physical isolation and no other Bletilla striata species were found within a radius of 1000m.

[0066] 2. Collection and collection of seed pods

[0067] During the peak flowering period from April to May, select strong and healthy plants for pollination and leave 2 to 3 pods, and thin out the inflorescences of weak plants.

[0068] 3. Storage of pods and collection of seeds

[0069] Around early November of the year of pollination, when the pods begin to turn yellow, harvest the plump and ripe pods, place them in a cool place to dry, and store them in bottles in a refrigerator at 4°C.

[0070] 4. Sowing

[0071] ①Sowing time: When the minimum temperature is 15℃ or above and the average daily temperature reaches about 24℃ (around April in Hangzhou), direct sowing of Bletilla striata seeds is carried out.

[0072] ② Establishing the seedbed: Establish a seedbed in the greenhouse, with a width of 1.5 to 2 meters and a length determined by the length of the greenhouse. Level and compact the seedbed, spray with insecticide (a dilution of 250 ml of 40% phoxim emulsifiable concentrate in 100 liters of water per acre), and then lay a layer of non-woven fabric on the seedbed, ensuring it adheres tightly to the topsoil. Surround the seedbed with thin bricks for easier management and operation.

[0073] ③ Preparation of nutrient soil: The seedling substrate on the seedbed consists of a bottom substrate containing bacteria and an upper substrate containing bacteria;

[0074] First, lay a 6-7cm thick bottom matrix on the non-woven fabric. The bottom matrix formula is peat: vermiculite: mature organic fertilizer: mud and sand = 5:1:1:3 (volume ratio), spray 10 9 CFU / mL / ml of Bacillus velezensis bacterial liquid; the Bacillus velezensis bacterial liquid: bottom matrix = 1 / 500 (V / V); then sprinkle with clean water and stir evenly to make the moisture content of the bottom matrix reach 60-70%, to obtain a bacteria-containing bottom matrix.

[0075] The formula of the upper matrix is peat: vermiculite: mature organic fertilizer = 6:3:1 (volume ratio), spray 10 9 cfu / ml of Velez bacillus liquid, wherein the Velez bacillus liquid: upper layer matrix = 1 / 500 (V / V); then sprinkle with clean water and stir evenly to make the water content reach 60-70% to obtain a bacteria-containing upper layer matrix.

[0076] The upper bacterial substrate is laid on the lower bacterial substrate with a thickness of 5 to 6 cm, and then compacted appropriately in a conventional manner, generally to 85 to 90% of the original thickness after compaction; nutrient soil is obtained; at this point, the thickness of the entire seedling substrate is generally about 10 cm or more.

[0077] ④Sowing method:

[0078] Mix 1.5 grams of Bletilla striata seeds with 10 grams of talcum powder, and sieve through 100 mesh; then sprinkle evenly on the surface of the nutrient soil per square meter of the seedbed to complete the sowing; then lay a thin layer (about 0.5 cm thick) of the upper matrix.

[0079] ⑤ Set up sunshade facilities such as sunshade nets:

[0080] A sunshade net with a shading rate of 75% is set on the top of the seedbed. Additional sunshade facilities need to be added during high temperatures in summer to ensure that the intensity of light in the greenhouse on sunny days does not exceed 15,000 lux.

[0081] 5. Seedbed Management

[0082] Maintain appropriate light, temperature, humidity, and fertilization as follows:

[0083] ① Lighting: natural light, with sunshade nets;

[0084] ② Temperature: It is best to keep the temperature in the greenhouse at around 25℃. In addition to adding sunshade facilities during high temperatures in summer, attention should be paid to greenhouse ventilation.

[0085] Cool down to prevent high temperature from burning the seedlings.

[0086] ③Humidity: Water at the right time to keep the soil moisture content between 13.5% and 22%.

[0087] ④ Fertilization: After 4 true leaves grow (about 50 days after sowing), spray the diluted fertilizer containing 10 9 CFU / mL / ml of Bacillus velezensis bacterial solution in 10% potassium fulvic acid nutrient solution.

[0088] Contains 10 9 The preparation method of 10% potassium fulvic acid nutrient solution containing CFU / mL / ml of Bacillus velezensis bacterial liquid is as follows: first, potassium fulvic acid and water are mixed in a mass ratio of 1:4 to obtain 20% potassium fulvic acid nutrient solution; then, the 20% potassium fulvic acid nutrient solution is mixed with 2*10 9 CFU / mL / ml Bacillus velezensis bacterial liquid was mixed in equal volume ratio.

[0089] Each square meter of seedbed contains 10 9 The amount of 10% potassium fulvic acid nutrient solution for CFU / mL / ml Bacillus velezensis bacterial solution is 2 to 2.5 ml.

[0090] Generally diluted 50 to 100 times by volume.

[0091] ⑤ Combing seedlings: According to the emergence of seedlings in the seedbed, follow the routine and promptly remove the diseased seedlings (i.e., yellow leaves); when the regional density is significantly higher than the surrounding density, remove the weak seedlings with poor growth until the density is basically the same.

[0092] 6 Transplanting and foster care

[0093] Seven to ten days after sowing, Bletilla seeds begin to green. Three weeks after sowing, seeds begin to germinate. Thirty days after sowing, the first leaves appear. After about seven months of cultivation, the average pseudobulb diameter of seedlings grown from seeds reaches 7.62mm.

[0094] When the pseudobulbs of Bletilla striata seedlings reach more than 10mm, they are considered to be strong and can be directly used as field planting production seedlings, which generally account for 15-20% of the total seedlings. The remaining Bletilla striata seedlings with pseudobulb diameters of more than 6mm (i.e., Bletilla striata seedling pseudobulb diameters of 6-10mm) are transplanted as foster planting seedlings.

[0095] Pseudobulb diameter (mm) = (pseudobulb long diameter + short diameter) / 2.

[0096] The specific foster care methods are as follows:

[0097] ①. Seedbed Establishment: The foster seedbed should be established on relatively high and dry land that is not prone to waterlogging. Sandy loam rich in humus is preferred. The field should be slightly bun-shaped, 1.1-1.2 meters wide, with furrows 0.25-0.3 meters wide and 22-25 cm deep.

[0098] ②. Base fertilizer: Apply 35 kg of calcium magnesium phosphate fertilizer (effective phosphorus pentoxide ≥ 18.0%), 5 to 7.5 kg of potassium sulfate compound fertilizer (N-P2O5-K2O, 15-15-15), and 1500 kg of decomposed organic fertilizer per mu, and harrow them with a micro-tiller.

[0099] ③. Planting: The planting density is 10-12*8-10cm. Pinch the bulb with your thumb and index finger and push it into the soil 1.5-2.5cm, then turn your finger back and gently press the soil.

[0100] Light, temperature, humidity and fertilization: same as the above seedbed management.

[0101] The transplant survival rate is 98%.

[0102] Comparative Example 1: The spraying of the Bacillus velezensis liquid onto the bottom substrate and the upper substrate was omitted, and the rest was the same as Example 1.

[0103] The results are as follows: After about 7 months of cultivation, the average diameter of the pseudobulbs of Bletilla striata seedlings was 7.06 mm.

[0104] Comparative Example 2: The prior spraying of the Bacillus Velez subtilis solution on the bottom substrate and the upper substrate was omitted. Instead, on the 10th day after sowing, the same amount of the Bacillus Velez subtilis solution as in Example 1 was sprayed on the thin layer used to cover the seeds. The rest was the same as in Example 1.

[0105] The results are as follows: After about 7 months of cultivation, the average diameter of the pseudobulbs of Bletilla striata seedlings was 7.22 mm.

[0106] Comparative Example 3-1: The ratio of "Bacillus velez bacterial solution: bottom layer matrix" was changed from 1 / 500 (V / V) to "1 / 1000 (V / V)", and the ratio of "Bacillus velez bacterial solution: upper layer matrix" was also changed from 1 / 500 (V / V) to "1 / 1000 (V / V). The rest was the same as in Example 1.

[0107] The results are as follows: After about 7 months of cultivation, the average diameter of the pseudobulbs of Bletilla striata seedlings was 7.23 mm.

[0108] In Comparative Example 3-2, the ratio of "Bacillus velez bacterial solution: bottom layer matrix" was changed from 1 / 500 (V / V) to "2 / 500 (V / V)", and the ratio of "Bacillus velez bacterial solution: upper layer matrix" was also changed from 1 / 500 (V / V) to "2 / 500 (V / V)", and the rest was the same as in Example 1.

[0109] The results are as follows: After about 7 months of cultivation, the average diameter of the pseudobulbs of Bletilla striata seedlings is 7.60 mm.

[0110] Comparative Example 4: The spraying of the Bacillus Velezii liquid on the bottom matrix and the upper matrix was cancelled, and the "containing 10 9 The "10% potassium fulvate nutrient solution containing a CFU / mL / ml Bacillus velezensis bacterial solution" was changed to a "200 ppm concentration of potassium dihydrogen phosphate nutrient solution", and the amount of nutrient solution remained unchanged, still 2 to 2.5 ml per square meter of seedbed; the rest was the same as in Example 1.

[0111] The results are as follows: After about 7 months of cultivation, the average diameter of the pseudobulbs of Bletilla striata seedlings was 5.47 mm.

[0112] Finally, it should be noted that the above examples are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above examples and is subject to numerous variations. All variations that can be directly derived or conceived by a person of ordinary skill in the art from the disclosure of the present invention are considered to be within the scope of protection of the present invention.

Claims

1. A method for direct seeding and raising seedlings of Bletilla striata seeds using a substrate containing Bacillus velezensis, comprising obtaining Bletilla striata seeds, sowing, seedbed management, transplanting and fostering; characterized in that: The nutrient soil on the seedbed is composed of a bottom layer matrix containing bacteria and an upper layer matrix containing bacteria; First, lay a 6-7 cm thick bottom matrix on the non-woven fabric; the bottom matrix consists of peat: vermiculite: mature organic fertilizer: sediment = 5: (1 ± 0.1): (1 ± 0.1): (3 ± 0.3) by volume, and spray 10 9 CFU / mL of Bacillus velezensis ( Bacillus velezensis ) bacterial solution; the Bacillus Velez bacterial solution: bottom matrix = 1~2 / 500, V / V; then sprinkle with water and stir evenly until a moisture content of 60~70% of the bacterial bottom matrix is obtained; The upper matrix is composed of peat: vermiculite: mature organic fertilizer = 6: (3 ± 0.3): (1 ± 0.1) by volume. Spray 10 9 cfu / mL of Bacillus velezensis bacterial liquid, wherein the Bacillus velezensis bacterial liquid: the upper layer matrix = 1-2 / 500, V / V; then sprinkle with clean water and stir evenly until a bacterial upper layer matrix with a moisture content of 60-70% is obtained; The upper layer of the bacterial substrate is laid on the lower layer of the bacterial substrate to a thickness of 5 to 6 cm, and then compacted to obtain nutrient soil; The sowing is: 1.1) Set the sowing time: When the minimum temperature of the day is ≥15℃ and the average temperature is 24±3℃, sow the seeds of Bletilla striata. 1.2) Establishing the seedbed: Establish a seedbed in the greenhouse and lay non-woven fabric on the seedbed; 1.3) Preparation of nutrient soil; 1.4) Sowing method: Add 1.5±0.1g of Bletilla striata seeds and 10±0.5g of talcum powder, mix well, and sieve; then evenly sprinkle on the surface of the nutrient soil per square meter of the seedbed to complete the sowing; then lay a thin layer of top substrate; 1.5) Erect sunshade facilities: Install sunshades on top of the seedbed to ensure that the intensity of sunlight in the greenhouse does not exceed 15,000 lux on sunny days; The seedbed management is as follows: Set appropriate light, temperature, humidity and fertilization as follows: Light: natural light; Temperature: Keep the temperature in the greenhouse at 25±2℃; Humidity: Sprinkle water in time to maintain the soil moisture content at 13.5~22%; Fertilization: starting from the growth of 4 true leaves, spray the diluted nutrient solution once every 8 to 10 days; the nutrient solution contains 10 9 CFU / mL Velezella Bacillus velezensis ) 10% potassium fulvic acid nutrient solution of bacterial liquid; The containing 10 9 CFU / mL Velezella Bacillus velezensis The preparation method of 10% potassium fulvic acid nutrient solution of bacterial liquid is as follows: first, potassium fulvic acid and water are mixed in a mass ratio of 1:4 to obtain 20% potassium fulvic acid nutrient solution; then, the 20% potassium fulvic acid nutrient solution is mixed with 2×10 9 CFU / mL Velezella Bacillus velezensis ) The bacterial solutions were mixed in equal volume ratios; Use 2-2.5 mL of nutrient solution per square meter of seedbed; Described transplanting and foster care are: When the pseudobulbs of Bletilla striata seedlings reach more than 10 mm, they can be directly used as seedlings for field planting; When the pseudobulb size of Bletilla striata seedlings reaches 6-10 mm, they are used as foster plant seedlings.

2. The method for direct seeding and raising seedlings of Bletilla striata seeds containing a Bacillus Velezii matrix according to claim 1, characterized in that: The step 1.2) is as follows: establishing a seedbed in the greenhouse with a width of 1.5 to 2 meters, leveling and compacting the seedbed, spraying pesticides, and then laying a layer of non-woven fabric on the seedbed, with the non-woven fabric tightly attached to the topsoil of the seedbed.

3. The method for direct seeding and raising seedlings of Bletilla striata seeds containing a Bacillus Velezii matrix according to claim 2, characterized in that: Step 1.5) is to set a sunshade net with a shading rate of 75% on the top of the seedbed, and add sunshade facilities in summer to ensure that the intensity of light in the greenhouse on sunny days does not exceed 15,000 lux.

4. The method for direct seeding and raising seedlings of Bletilla striata seeds containing a Bacillus Velezii matrix according to claim 3, wherein: Seedbed management also includes thinning out seedlings: pulling out diseased seedlings; when the regional density is significantly higher than the surrounding density, pull out the weak seedlings that grow poorly until the density is basically the same.

5. The method for direct seeding and raising seedlings of Bletilla striata seeds containing the Bacillus Velezii matrix according to any one of claims 1 to 4, characterized in that The foster care methods are: Seedbed establishment: The foster seedbed should be established on a relatively high and dry plot of land that is not prone to waterlogging. Sandy loam rich in humus is preferred. The width of the field should be 1.1-1.2 meters, the width of the ditch should be 0.25-0.3 meters, and the depth of the ditch should be 22-25 cm. Base fertilizer: 35kg of calcium magnesium phosphate fertilizer, 5-7.5kg of potassium sulfate compound fertilizer, and 1500kg of decomposed organic fertilizer per mu, harrowed with a micro-tillage machine; Planting: Planting density: row spacing 10-12 × 8-10 cm, bulbs buried 1.5-2.5 cm deep; Light, temperature, humidity and fertilization: Same as the above seedbed management.